I called ZF today and talked with a very friendly and competent ZF engineer. He told me that 350 lbft @ the wheels ( 530 nm crank ) would be a good and reliable number for the 335i AT ( ZF HP21 ). 380 lbft @ the wheels and more would be a very different story and he gave me a contact where to go to discuss about having my steptronic upgraded.

Now, Shiv, would it be possible to get a flat torque curve, max. 350 lbft tourqe @ the wheels V2 map from you still providing 380 - 400 hp crank top end power ?

I called ZF today and talked with a very friendly and competent ZF engineer. He told me that 350 lbft @ the wheels ( 530 nm crank ) would be a good and reliable number for the 335i AT ( ZF HP21 ). 380 lbft @ the wheels and more would be a very different story and he gave me a contact where to go to discuss about having my steptronic upgraded.

Now, Shiv, would it be possible to get a flat torque curve, max. 350 lbft tourqe @ the wheels V2 map from you still providing 380 - 400 hp crank top end power ?

Thank you.

Cheers
Eugen

I'm sitting here looking at my dyno graph from v1.4. My wtq is only above 350 from about 2k-3800 rpm (max 379). Maybe this isn't what your looking for but I'm sure it would be easy with v2's sixteen point power adjustability to simply only put 100% power from 4k-7k rpm and adjust down to maybe 80% from 2-4k (?). Just guessing here. With v2 you probably get more wtq though so you would just adjust these number slightly.

I called ZF today and talked with a very friendly and competent ZF engineer. He told me that 350 lbft @ the wheels ( 530 nm crank ) would be a good and reliable number for the 335i AT ( ZF HP21 ). 380 lbft @ the wheels and more would be a very different story and he gave me a contact where to go to discuss about having my steptronic upgraded.

Now, Shiv, would it be possible to get a flat torque curve, max. 350 lbft tourqe @ the wheels V2 map from you still providing 380 - 400 hp crank top end power ?

Thank you.

Cheers
Eugen

Well, I guess the BavDom/VQmtuning stage 2 (420wlbs) will need to wait until the transmission is toughened up.....

I called ZF today and talked with a very friendly and competent ZF engineer. He told me that 350 lbft @ the wheels ( 530 nm crank ) would be a good and reliable number for the 335i AT ( ZF HP21 ). 380 lbft @ the wheels and more would be a very different story and he gave me a contact where to go to discuss about having my steptronic upgraded.

Now, Shiv, would it be possible to get a flat torque curve, max. 350 lbft tourqe @ the wheels V2 map from you still providing 380 - 400 hp crank top end power ?

I'm sitting here looking at my dyno graph from v1.4. My wtq is only above 350 from about 2k-3800 rpm (max 379). Maybe this isn't what your looking for but I'm sure it would be easy with v2's sixteen point power adjustability to simply only put 100% power from 4k-7k rpm and adjust down to maybe 80% from 2-4k (?). Just guessing here. With v2 you probably get more wtq though so you would just adjust these number slightly.

1+

The approach is correct, we will be able to adjust the torque curve exactly with PROcede V2. Thus I have no personal dyno, I would prefer a map or settings from Vishnu.

Upgrading the steptronic has to be checked from a ZF service location. The ZF engineer expected that 6HP28 parts could be used. A ZF service location is 10 miles apart from my home.

Anyway, I will not upgrade the steptronic. I will use the reliable engine tune. BTW, the torque value is measured on the input side of the gearbox / steptronic, we discussed a while ago about on the forum.

Oh nono, my friend, just asking for a favor. And only for scientific reasons, of course

Quote:

Originally Posted by e.n335

We have the 6HP19TU ( = 6HP21 ) installed. The approach is correct, we will be able to adjust the torque curve exactly with the V2. Thus I have no personal dyno, I would prefer a map or settings from Vishnu.

Upgrading the steptronic has to be checked from a ZF service location. The ZF engineer expected that 6HP28 parts could be used. A ZF service location is 10 miles apart from my home.

Anyway, I will not upgrade the steptronic. I will use the reliable engine tune. BTW, the torque value is measured on the input side of the gearbox / steptronic, we discussed a while ago about on the forum.

The manual gearbox is much stronger.

- Eugen

Anyway, even if U dont upgrade your steptronic, U could gather some info for us. Again, for simply scientific reasons, of course. But maybe someone would not mind to spend some more $$ and leave his V2 curve the natural way.

Oh nono, my friend, just asking for a favor. And only for scientific reasons, of course

Anyway, even if U dont upgrade your steptronic, U could gather some info for us. Again, for simply scientific reasons, of course. But maybe someone would not mind to spend some more $$ and leave his V2 curve the natural way.

+1, I would also like to know the cost of the upgraded AT as I'm planning on bigger turbo's in the future and it seems you have an inside track eugen.

Having the cap on the torque level without affecting the max power is what the adjustability of torque in V2 is meant for. You can do it and the respective values that will match the ZF engineer's "safe limit" will surely be public info on this forum.

I called ZF today and talked with a very friendly and competent ZF engineer. He told me that 350 lbft @ the wheels ( 530 nm crank ) would be a good and reliable number for the 335i AT ( ZF HP21 ). 380 lbft @ the wheels and more would be a very different story and he gave me a contact where to go to discuss about having my steptronic upgraded.

Now, Shiv, would it be possible to get a flat torque curve, max. 350 lbft tourqe @ the wheels V2 map from you still providing 380 - 400 hp crank top end power ?

Thank you.

Cheers
Eugen

I would ask the question which far more important which is duty cycle. Are they not recommending you exceed 350 ft-lb because of clutch pack slippage problem or does it have something to do with fatigue? If the life of the transmission is reduced by 30% then I could live with this as I probably hammering everything else as well.

Actually, google.com the 6HP28 transmission. the e92 coupe 335i transmission has a wtq rating of 332 ftlbs.....Someone better work on an upgrade and fast.

The 28 has a capability of 515 ftlbs of torque...much better for our group...buuuuuuut the problem is how to find a shop, cost, and pracitcality of the issue.

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